In the past few decades, the use of nano-based products has been expanding, subsequently increasing the risk of aquatic contamination by nanoparticles (NPs). Consequently, it is important to assess the potential risks of environmentally realistic concentrations of NPs. Leaf litter decomposition, a fundamental ecological process in headwater streams, is governed mainly by fungi. In this study, copper oxide nanoparticles (CuO NPs) were synthesised, and the influence of short term exposure to low concentrations of copper oxide nanoparticles on leaf litter decomposition and fungal reproduction (sporulation) was assessed. A cosmopolitan aquatic fungal decomposer species Articulospora tetracladia was used to assess litter decomposition upon exposure to CuO NPs (0.00, 0.04, 0.08 and 0.12 mg L⁻¹) for a short time period (1, 2, 3 and 4 days). Concentrations and exposure time of NPs affected both leaf litter decomposition and sporulation. A significant difference in leaf litter decomposition and fungal sporulation was observed between the control (0.0 mg L⁻¹) and all concentrations tested but not between 0.04, 0.08 and 0.12 mg L⁻¹ of NPs. All the exposure time points (1, 2, 3 and 4 days) had a significant impact on sporulation; however a significant difference in leaf litter mass loss was seen between all time points except for between 2 and 3 days. Overall, our study provides a novel insight into the potential risk of short-term exposure to environmentally realistic concentrations of CuO NPs on the ecological performance of a cosmopolitan freshwater fungus.

中文翻译：

---

短期暴露于低浓度的氧化铜纳米颗粒会负面影响大都会淡水真菌的生态性能。

在过去的几十年中，基于纳米的产品的用途不断扩大，从而增加了纳米颗粒（NP）对水生生物的污染风险。因此，重要的是评估在环境上现实的NP浓度的潜在风险。凋落物分解是源头水流中的基本生态过程，主要由真菌控制。在这项研究中，合成了氧化铜纳米粒子（CuO NPs），并评估了短期暴露于低浓度的氧化铜纳米粒子对叶片凋落物分解和真菌繁殖（造粒）的影响。大都会水生真菌分解物种四叶草（Articulosporatetracladia）用于评估暴露于CuO NPs（0.00、0.04、0.08和0.12 mg L ^-1时的凋落物分解））短时间段（1、2、3和4天）。NP的浓度和暴露时间影响叶片凋落物的分解和孢子形成。在对照（0.0mg L ^-1）和所有测试浓度之间观察到叶凋落物分解和真菌孢子形成的显着差异，但在NP的0.04、0.08和0.12mg L ^-1之间未观察到差异。所有的暴露时间点（1、2、3和4天）对孢子形成有显着影响。然而，除2至3天外，所有时间点之间的凋落物质量损失均存在显着差异。总体而言，我们的研究提供了一个新颖的见解，即短期暴露于环境现实浓度的CuO NPs对大都会淡水真菌的生态性能的潜在风险。